ATMEGA644P-A15MZ Atmel, ATMEGA644P-A15MZ Datasheet - Page 105

• Manufacturer Part Number: ATMEGA644P-A15MZ
• Description: MCU AVR 64KB FLASH 16MHZ 44QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644P-A15MZ

• Package / Case: 44-VQFN Exposed Pad
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 32
• Eeprom Size: 2K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Program Memory Size: 64KB (64K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7674F–AVR–09/09
Table 13-7 on page 105
to phase correct PWM mode.
Table 13-7.
Note:
• Bits 3:2 – Res: Reserved Bits
These bits are reserved bits in the ATmega164P/324P/644P and will always read as zero.
• Bits 1:0 – WGM01:0: Waveform Generation Mode
Combined with the WGM02 bit found in the TCCR0B Register, these bits control the counting
sequence of the counter, the source for maximum (TOP) counter value, and what type of wave-
form generation to be used, see
Timer/Counter unit are: Normal mode (counter), Clear Timer on Compare Match (CTC) mode,
and two types of Pulse Width Modulation (PWM) modes (see
122).
Table 13-8.
Notes:
Mode
COM0B1
0
1
2
3
4
5
6
7
0
0
1
1
1. A special case occurs when OCR0B equals TOP and COM0B1 is set. In this case, the Com-
1. MAX
2. BOTTOM = 0x00
WGM2
pare Match is ignored, but the set or clear is done at TOP. See
page 100
0
0
0
0
1
1
1
1
Compare Output Mode, Phase Correct PWM Mode
Waveform Generation Mode Bit Description
COM0B0
for more details.
= 0xFF
WGM1
0
1
0
1
0
0
1
1
0
0
1
1
shows the COM0B1:0 bit functionality when the WGM02:0 bits are set
Description
Normal port operation, OC0B disconnected.
Reserved
Clear OC0B on Compare Match when up-counting. Set OC0B on
Compare Match when down-counting.
Set OC0B on Compare Match when up-counting. Clear OC0B on
Compare Match when down-counting.
WGM0
Table 13-8 on page
0
1
0
1
0
1
0
1
Timer/Counter
Mode of
Operation
Normal
PWM, Phase
Correct
CTC
Fast PWM
Reserved
PWM, Phase
Correct
Reserved
Fast PWM
ATmega164P/324P/644P
105. Modes of operation supported by the
OCRA
OCRA
OCRA
0xFF
0xFF
0xFF
TOP
–
–
“Modes of Operation” on page
(1)
“Phase Correct PWM Mode” on
Immediate
Immediate
Update of
BOTTOM
BOTTOM
OCRx at
TOP
TOP
–
–
Set on
TOV Flag
BOTTOM
BOTTOM
MAX
MAX
MAX
TOP
–
–
(1)(2)
105